Turbine housing of turbocharger for vehicle

ABSTRACT

A turbine housing of a turbocharger for a vehicle that may be connected to an exhaust manifold and in which a turbine wheel may be rotated using kinetic energy of exhaust gas therein, may include a turbine wheel accepting portion having a circular hole shape so as to receive the turbine wheel therein, a scroll portion surrounding the turbine wheel accepting portion therein, wherein an exhaust gas passage may be formed along a rotating direction of the turbine wheel through the scroll portion, a partition dividing the exhaust gas passage of the scroll portion into at least two passages, and a slit formed at the partition in a radial direction of the partition.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No.10-2011-0112248 filed in the Korean Intellectual Property Office on Oct.31, 2011, the entire contents of which is incorporated herein for allpurposes by this reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a turbine housing of a turbocharger fora vehicle. More particularly, the present invention relates to a turbinehousing of a turbocharger for a vehicle that improves durability.

2. Description of Related Art

Generally, engine output per cycle can be increased when pressure ofintake air flowing into a cylinder of an engine is increased to higherthan atmospheric pressure and an air amount in the cylinder isincreased. This is called supercharging. Mechanical superchargingdeteriorates thermal efficiency even though crankshaft power isincreased since output of a crankshaft is used for compressing theintake air.

In order to solve the problem, the turbocharger has been developed.According to the turbocharger, a compressor fixedly connected with anexhaust turbine feeds air into the cylinder when the exhaust turbine isoperated by energy from exhaust gas. Therefore, engine output isimproved. The turbocharger is widely used with diesel engines where aknocking problem does not generally occur as opposed to a gasolineengine where knocking occurs if the pressure in the cylinder isexcessively increased by supercharging.

In detail, in the turbocharger, a turbine wheel that recovers exhaustenergy and a compressor wheel that delivers compressed air to thecylinder are disposed on respective ends of the same shaft, and ahousing for leading flow of the exhaust gas and the air covers eachwheel. Particularly, the turbine housing is divided into a single scrolltype having one exhaust gas passage and a twin scroll type having twoexhaust gas passages divided by a partition. The twin scroll typeprevents exhaust interference of the engine and efficiently uses a pulseeffect of the exhaust, and thus rotation efficiency of the turbine wheelcan be improved.

However, a pressure difference between cylinders of the twin scrollbecomes larger in comparison with that of the single scroll, and thus aside force due to exhaust pulsation is exerted on the partition.Therefore, a crack in the partition often occurs. In addition,durability of the partition may be weakened by repeated expansion andcompression due to an abnormal temperature inversion phenomenon of innerand outer portions of the scroll.

The information disclosed in this Background of the Invention section isonly for enhancement of understanding of the general background of theinvention and should not be taken as an acknowledgement or any form ofsuggestion that this information forms the prior art already known to aperson skilled in the art.

BRIEF SUMMARY

Various aspects of the present invention are directed to providing aturbine housing of a turbocharger for a vehicle having advantages ofimproving durability of a partition of the turbine housing as a twinscroll type.

In an aspect of the present invention, a turbine housing of aturbocharger for a vehicle that is connected to an exhaust manifold andin which a turbine wheel is rotated using kinetic energy of exhaust gastherein, may include a turbine wheel accepting portion having a circularhole shape so as to receive the turbine wheel therein, a scroll portionsurrounding the turbine wheel accepting portion therein, wherein anexhaust gas passage is formed along a rotating direction of the turbinewheel through the scroll portion, a partition dividing the exhaust gaspassage of the scroll portion into at least two passages, and a slitformed at the partition in a radial direction of the partition.

The partition may include a scroll wall extending from an inner surfaceof the scroll portion toward a center of the turbine housing, and ascroll tip formed at an end portion of the scroll wall, wherein thescroll tip is thinner than the scroll wall.

The scroll portion may include inner rims extending from an innersurface of the turbine housing and the scroll tip is disposed betweenthe rims to deliver the exhaust gas to the turbine wheel throughopenings formed between the rims and the scroll tip.

A diameter of the rims is shorter than that of the scroll tip.

At least a portion of the exhaust gas passage of the scroll portion isopen toward the turbine wheel so as to deliver the kinetic energy of theexhaust gas to the turbine wheel.

A width of the slit is constant along the radial direction of thepartition.

The width of the slit is between approximately 0.2 mm and approximately0.4 mm.

The methods and apparatuses of the present invention may have otherfeatures and advantages which will be apparent from or are set forth inmore detail in the accompanying drawings, which are incorporated herein,and the following Detailed Description, which together serve to explaincertain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a turbine housing of a turbocharger fora vehicle according to an exemplary embodiment of the present invention.

FIG. 2 is a schematic diagram of a turbocharger according to anexemplary embodiment of the present invention.

FIG. 3 is an enlarged cross-sectional view of a scroll portion accordingto an exemplary embodiment of the present invention.

FIG. 4 is a perspective view of a partition taken along a line A-A inFIG. 2.

It should be understood that the appended drawings are not necessarilyto scale, presenting a somewhat simplified representation of variousfeatures illustrative of the basic principles of the invention. Thespecific design features of the present invention as disclosed herein,including, for example, specific dimensions, orientations, locations,and shapes will be determined in part by the particular intendedapplication and use environment.

In the figures, reference numbers refer to the same or equivalent partsof the present invention throughout the several figures of the drawing.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of thepresent invention(s), examples of which are illustrated in theaccompanying drawings and described below. While the invention(s) willbe described in conjunction with exemplary embodiments, it will beunderstood that the present description is not intended to limit theinvention(s) to those exemplary embodiments. On the contrary, theinvention(s) is/are intended to cover not only the exemplaryembodiments, but also various alternatives, modifications, equivalentsand other embodiments, which may be included within the spirit and scopeof the invention as defined by the appended claims.

FIG. 1 is a perspective view of a turbine housing of a turbocharger fora vehicle according to an exemplary embodiment of the present invention.

As shown in FIG. 1, a turbine housing 10 of a turbocharger for a vehicleaccording to an exemplary embodiment of the present invention isconnected with an exhaust manifold 30, and includes a scroll portion 11and a turbine wheel accepting portion 15.

The turbine housing 10 is adapted to receive exhaust gas from theexhaust manifold 30. In addition, the turbine housing 10 is adapted tooperate a turbine by using kinetic energy of the exhaust gas.

The turbine wheel accepting portion 15 is formed with a circular holeshape penetrating the turbine housing 10.

The scroll portion 11 forms passages to flow the exhaust gas along anexterior circumference of the turbine wheel accepting portion 15.

FIG. 2 is a schematic diagram of a turbocharger according to anexemplary embodiment of the present invention.

As shown in FIG. 2, the scroll portion 11 includes a power delivery hole17, a partition 14, and a twin scroll 12, and a turbine wheel 16 isdisposed at the turbine wheel accepting portion 15.

The power delivery hole 17 is formed along an interior circumference ofthe scroll portion 11 such that an exhaust gas passage of the scrollportion 11 is opened toward the turbine wheel 16 with a predeterminedgap.

The partition 14 is formed to divide the exhaust gas passage of thescroll portion 11 into two passages, and the two passages divided by thepartition 14 are called the twin scroll 12. In addition, the partition14 protrudes from an interior surface of a radial outside portion of thescroll portion 11 to the proximity of the power delivery hole 17, andthus the twin scroll 12 is formed.

When the exhaust gas is delivered from the exhaust manifold 30 to theturbine housing 10, the exhaust gas rotates around the turbine wheel 16along the twin scroll 12. At this time, power of the exhaust gas isdelivered to the turbine wheel 16 through the power delivery hole 17.Thus, the turbine wheel 16 is rotated. Arrows in FIG. 2 represent theflow of the exhaust gas supplied from the exhaust manifold 30.

The torque of the turbine wheel 16 rotated by the above-mentionedoperation is delivered to a compressor wheel 20, and the compressed airgenerated by rotation of the compressor wheel 20 is delivered to acylinder. An operation of the turbocharger that improves output of anengine by these processes is well-known to a person of ordinary skill inthe art such that a detailed description thereof will be omitted.

FIG. 3 is an enlarged cross-sectional view of a scroll portion accordingto an exemplary embodiment of the present invention.

As shown in FIG. 3, the partition 14 dividing the exhaust gas passage ofthe scroll portion 11 so as to form the twin scroll 12 includes a scrollwall 14 a and a scroll tip 14 b.

The scroll wall 14 a refers to a part of the partition 14 protruded fromthe interior surface of the radial outside of the scroll portion 11. Inaddition, the scroll tip 14 b refers to another part of the partition 14close to the power delivery hole 17. In other words, the scroll tip 14 bthat is close to the turbine wheel 16 is heated faster than the scrollwall 14 a. Further, the scroll tip 14 b that is formed thinner than thescroll wall 14 a emits heat easily and is cooled quickly. Therefore, thecompression and the expansion of the scroll tip 14 b can be excessivelygenerated in comparison with the scroll wall 14 a.

In an exemplary embodiment of the present invention, the scroll portion11 includes inner rims 25 extending from an inner surface of the turbinehousing 10 and the scroll tip 14 b is disposed between the rims 25 todeliver exhaust gas to the turbine wheel 16 through openings formedbetween the rims 25 and the scroll tip 14 b.

Diameter of the rims 25 may be shorter than that of the scroll tip 14 b.

FIG. 4 is a perspective view of a partition taken along a line A-A inFIG. 2.

As shown in FIG. 4, the partition 14 viewed along the line A-A in FIG. 2may have an annular shape and includes a slit 18.

At least one of slits 18 is formed radially at the partition 14 of theannular shape. In addition, each slit 18 is a narrow gap formed from thescroll tip 14 b to the scroll wall 14 a so as to cut the partition 14.Further, the width of the slit 18 may be about 0.2-0.4 mm, andpreferably about 0.3 mm.

Three straight slits 18 cutting the partition 14 are shown in FIG. 4,but the number and shape of the slits 18 are not limited to theexemplary embodiment shown in FIG. 4. The number and shape of the slits18 can be changed variously by a person of ordinary skill in the art.

As described above, since the slits 18 are formed at the partition 14,durability of the partition 14 that experiences repeated expansion andcompression can be improved. In other words, since occurrence of a crackat the partition 14 is prevented, deterioration of the turbocharger canbe reduced.

While this invention has been described in connection with what ispresently considered to be practical exemplary embodiments, it is to beunderstood that the invention is not limited to the disclosedembodiments, but, on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

For convenience in explanation and accurate definition in the appendedclaims, the terms “upper”, “lower”, “inner” and “outer” are used todescribe features of the exemplary embodiments with reference to thepositions of such features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of thepresent invention have been presented for purposes of illustration anddescription. They are not intended to be exhaustive or to limit theinvention to the precise forms disclosed, and obviously manymodifications and variations are possible in light of the aboveteachings. The exemplary embodiments were chosen and described in orderto explain certain principles of the invention and their practicalapplication, to thereby enable others skilled in the art to make andutilize various exemplary embodiments of the present invention, as wellas various alternatives and modifications thereof. It is intended thatthe scope of the invention be defined by the Claims appended hereto andtheir equivalents.

What is claimed is:
 1. A turbine housing of a turbocharger for a vehiclethat is connected to an exhaust manifold and in which a turbine wheel isrotated using kinetic energy of exhaust gas therein, the turbine housingcomprising: a turbine wheel accepting portion having a circular holeshape so as to receive the turbine wheel therein; a scroll portionsurrounding the turbine wheel accepting portion therein, wherein anexhaust gas passage is formed along a rotating direction of the turbinewheel through the scroll portion; a partition dividing the exhaust gaspassage of the scroll portion into at least two passages; and a slitformed at the partition in a radial direction of the partition.
 2. Theturbine housing of claim 1, wherein the partition includes: a scrollwall extending from an inner surface of the scroll portion toward acenter of the turbine housing; and a scroll tip formed at an end portionof the scroll wall, wherein the scroll tip is thinner than the scrollwall.
 3. The turbine housing of claim 2, wherein the scroll portionincludes inner rims extending from an inner surface of the turbinehousing and the scroll tip is disposed between the rims to deliver theexhaust gas to the turbine wheel through openings formed between therims and the scroll tip.
 4. The turbine housing of claim 3, wherein adiameter of the rims is shorter than that of the scroll tip.
 5. Theturbine housing of claim 1, wherein at least a portion of the exhaustgas passage of the scroll portion is open toward the turbine wheel so asto deliver the kinetic energy of the exhaust gas to the turbine wheel.6. The turbine housing of claim 1, wherein a width of the slit isconstant along the radial direction of the partition.
 7. The turbinehousing of claim 6, wherein the width of the slit is betweenapproximately 0.2 mm and approximately 0.4 mm.